That’s actually exactly what you would expect to see if you browse directly to the IP address that the Arduino-server is running on. The data is showing the actual voltage value (scaled from 0 to 1023) on each of the pins. You’ll notice that if you refresh the page, the numbers will change slightly, depending on if you have floating voltages.

What the graph does, and the other examples above, is to very rapidly poll that page to get streaming data. This way you can have a graph or anything else on a webpage that uses real-time Arduino data. There is no need for an SD card.

If you’re seeing that data when visiting the IP address, everything should be working, so try hitting the “Start” button on the second example above. You should see the data coming in and being graphed (although note that the scaling of the graph may be way off depending on what values you are getting).

arduinoEthernetComCallback(‘{“A0″: 1023,”A1″: 718,”A2″: 543,”A3″: 468,”A4″: 358,”A5″: 324}’)

Using the JSON-P pattern above should make it possible for you to update the data without reloading the page each time.

You can look at my library here: https://github.com/sfentress/ArduinoEthernetCom

Or you can just update the sketch you are using to return data in a JSON-P format. The basic idea is simply that you load in the page from the Arduino as a new script and evaluate it with each update. When the script loads, it calls a method with all the updated data values.

Mike Brian

The simple server sketch linked above would only work connected directly to the computer, because it assignes itself a local IP, http://169.254.1.1.

However, you can certainly just plug the Arduino into your router and change the IP settings in the sketch to make it accessible from the internet, but you would either need to use a static IP address or use DHCP to find a dynamic IP address. The problem with the latter option is that you would need to know the new IP address in order to connect to it, so this wouldn’t be an easy permanent solution, but would be suitable for testing.

Once the Arduino is connected to the internet, it would work exactly as before, except that you probably wouldn’t be able to poll it several times a second as I do in the examples above, due to network latencies.

There are a number of resources that can be found online for learning how to connect an Arduino to the internet, such as this one, and there’s a DHCP library for obtain network configurations.

Now you can create basic examples of getting data from an Arduino with about 10 lines of JavaScript. You can look at the source of the example page at http://sfentress.github.com/ArduinoEthernetCom/example.html

http://groups.google.com/group/org-concord-sensor/browse_thread/thread/80602532466a8593